Answer:
Option (b) 36.7
Step-by-step explanation:
Data provided in the question:
Treatment 1 Treatment 2 Treatment 3 Treatment 4
Sample Size 50 18 10 17
Sample Mean 32 36 42 48
Now,
The overall mean is calculated as
=
Here, Xi = Sample mean
n = sample sizes
Thus,
Overall mean
= [ (50 × 32) + (18 × 36) + (10 × 42) + (17 × 48) ] ÷ [ 50 + 18 + 10 + 17 ]
= [ 1600 + 648 + 420 + 816 ] ÷ 95
= 36.67 ≈ 36.7
hence,
Option (b) 36.7
Total Surface Area = 375
You need to find the area of the ceiling, floor, the two rectangle walls and the two trapezoid walls
<u>Area of the ceiling:</u>
c = length * width
c = 9*6.5 = 58.5
<u>Area of the 2 rectangle walls:</u>
w = 2(length * width)
w = 2(9 * 8)
w = 2(72)
w = 144
<u>Area of floor:</u>
f = 9 * 7.5
f = 67.5
<u>Area of the two trapezoids:</u>
a = 6.5
b = 7.5
h = 7.5
Total Surface Area = c + w + f + t
Total Surface Area = 58.5 + 144 + 67.5 + 105
Total Surface Area = 375